Pressure sealing assemblies for rotary vane piston devices

ABSTRACT

Pressure sealing assemblies for the annular chambers of rotary vane piston motors, pumps or gas generators employing rotating sets of vane pistons moving in an annular chamber and alternately accelerating and decelerating while moving around the annular chamber. Dual sidewall units formed of interfitting sidewall assemblies relatively movable over short axial distances are employed to provide self-balancing pressure-sealing sliding contact with central, hub-type piston support members. Pressurized gas escaping radially inward from the annular chamber is conducted into flat, annular disk-shaped spaces between the dual sidewalls at each end of the piston chamber, urging the innermost sidewall of each sidewall unit into sliding, pressuresealing engagement with the central, hub-type piston support members. Interfitting, spoked, stepped-bridged hub-type assemblies are employed to anchor together as integral subassemblies the outer chamber sidewall at each end of the annular piston chamber with the inner chamber sidewall at the opposite end of the piston chamber. The radically outermost peripheral portions of each of these sidewall units flanking the piston chamber along its outer annular periphery are provided with conventional sealing rings and with a single toothed annular sealing ring mounted in a ring groove behind toothed flanges, next to the annular chamber, isolating the sector spaces between each vane piston and the next adjacent vane piston, and providing a highly effective pressure-sealing assembly for such rotary piston devices.

United States Patent [151 3,658,447

Bancroft [4 1 Apr. 25, 1972 [54] I PRESSURE SEALING ASSEMBLIES FOR vane piston motors, pumps or gas generators employing rotat- ROTARY V N ISTO D VICES 'ing sets of vane pistons moving in an annular chamber and alternately accelerating and decelerating while moving around inventor; Charles 39mm, 178 Ferris d I the annular chamber.' Dual sidewall units formed of inter- New Canaan, Conn 06340 fitting sidewall assemblies relatively movable over short axial [221 APL91970 distances are employed to provide self-balancing pressuresealing sliding contact with central, hub-type piston support members. Pressurized gas escaping radially inward from the annular chamber is conducted into flat, annular disk-shaped 521 u.s.c|. ..418/33,4l8/37,4l8/1'43 Spaces between the dual sidewalls at each end of the Piston 211 Appl. No.: 26,827

[51 Int. Cl ..F01 1/00, F03 3/00, F04 27/00 chamber, urging the innermost sidewall of each sidewall unit 581 Field oISearch ..4l8/37,33',35,38,143,36; into sliding, pressure-sealing engagement with the central,

l23/8.07,8. 47 hub-type piston support members. lnterfitting, spoked,-

stepped-bridged hub-type assemblies are employed to anchor [56] References Cited I r together as integral sub-assemblies the outer chamber sidewall at each end of the annular piston chamber with the inner UNITED STATES PATENTS chamber sidewall at the opposite end of the piston chamber. 2,544,480 3/1951 Bancroft ..41s/37 The radically outermost Peripheral Portions of each of these 2 553 954 5 195 Bancrofh 23 g 7 sidewall units flanking the piston chamber along its outer an- 2,228,193 1/1941 Bancroft... ..l'23/8 .47 nular periphery are provided with conventional sealing rings 2,270 493 1 1942 Ban ft 413 37 and.with a single toothed annular sealing ring mounted in a 2 544 431 3 1951 B ft 418/37 ring groove behind toothed flanges, next to the annular 2,547,374 4/l95l Carideo ..4l8/37 chamber, isolating the sector spaces between each vane piston and the next adjacent vane piston, and providing a highly ef- Primary Examiner-Carlton R. Croyle fective pressure-sealing assembly for such rotary piston Assistant Examiner-John J. Vrablik devices. Attorney-Mattern, Ware & Davis 15 Claims, 13 Drawing Figures ABSTRACT Pressure sealing assemblies for the annular chambers of rotary PATENTEDAPR 25 m2 SHEET 2 CF 5 AV l PRESSURE SEALING ASSEMBLIES FOR ROTARY VANE PISTON DEVICES BACKGROUND OF THE INVENTION sets of vane pistons are positioned for rotation, being mounted on annular or tubular sleeves or piston support members securing all pistons of each set in theirpredetermined angular positions, each equally spaced from the other pistons of that set around the periphery of the chamber. The pistons of successive different piston sets are successively interposed proceeding around the annular chamber, and are anchored to individual support plates or tubular sleeves, preferably interfitting with each other to form labyrinth seals retaining compression and combustion pressure within the sectors of the an-' nular chamber defined by its walls and the facing surfaces of the vane pistons. As described in my U.S. Pat. Nos. 2,061,131; 2,155,249 and 2,544,480, the changing acceleration and deceleration of the piston sets produced by the varying angular relationship between these piston sets and the crankshaft of the device depend upon connecting members rotatably mounted upon offset crankpins of the crankshaft and provided with pinion gear means engaging a stationary ring gear to produce rotation of the connecting member in a direction contrary to that of the crankshaft. These connecting members are provided with integral pivot pins on which are journaled pillow blocks" or crosshead bearing blocks in sliding an.

gagement with radial tracks or guideway slides formed on radial flange portions of the support members of each piston set. In this manner the internal rolling motion" of the con-v necting member within the stator-mounted stationary ring gear produces an epitrochoid" or hypotrochoid" curve about the maximum radial locus of these pivoting pins. The

angular acceleration and deceleration of the connecting member pins as they follow this path are transmitted by these radial guidewaysdirectly to the piston sets, producing corresponding angular acceleration and deceleration of the piston sets according to a predetermined pattern. The rolling engagement of the connecting members with the stator may be provided either by pinion-internal ring gear assemblies, or by trammel gear" means as described in my U.S. Pat. No. 3,231,531 and illustrated in FIG. 6 thereof by a lobed member 92d engaging a lobed track 98a, effectively forming a gear substitute. The successive corresponding positions of a connecting member 52 and several sets of vane pistons engaged therewith are shown in my U.S. Pat. No. 2,061,131 at FIGS. through 22, and in my U.S. Pat. No. 2,155,249 at FIGS. 11 through 23.

These rotary piston devices provide exceptional displacement for a given size and weight of engine, since the approaching pistons may be moved into face-to-face contact with each other, and may then be separated by large angular distances; the overlapping of these angular distances during successive expansion strokes of successive sets of vane pistons provides a volume substantially larger than the volume of the annular chamber swept by the piston sets. For this reason,

such devices may have very high volumetric efficiency and large displacement for a given size, limited only by the normal problems of pressure fluid sealing, dynamic balancing and lubrication against sliding friction encountered in all rotating machinery. In order to take advantage of these features while providing solutions to the practical problems, the present invention incorporates a number of useful innovations.

1n the rotary vane piston devices described in my copending United States patent application Ser. 750,084, filed Aug. 5th,

1968, issued as U.S. Pat. No. 3,544,242 on Dec. 1, 1970, the support members for each of the different sets of vane pistons incorporate annular portions facing inwardly and directly exposed to the compression or combustion pressures developed within the annular vane piston chambers, and these support members have opposite sections of substantially equal area to balance out the axial forces tending to produce longitudinal movement resulting from pressures within the chambers. Those support members thus form portions of the chamber sidewalls, and sealing rings are employed between them to retain pressures developed within the vane piston chamber. The sidewalls" enclosing the ends of the annular vane piston chambers in devices described in that copending patent application incorporate two or three annular segments of successively greater diameter, arrayed radially to form the end walls of these vane piston chambers.

SUMMARY OF THE lNVENTION In the rotary vane piston devices of the present invention, a single support member for a single set of vane pistons is employed to form an entire sidewall extending across one axial end of the annular vane piston chamber. A separate support member for a second set of vane pistons is employed to form the entire opposite sidewall extending across the opposite axial end of the annular vane piston chamber. These sidewalls are positioned in facing, sliding contact with the axial ends of the vane pistons of all sets.

Each piston-contacting sidewall forms the inner wall member of a pair of sidewalls comprising a dual sidewall unit. The outer sidewall of each unit is integrally assembled with and anchored to the inner sidewall of the other unit at the opposite end of the vane piston chamber by a stepped-bridge structure. This stepped-bridge structure interfits with a corresponding structure joining the opposite sidewalls of each paired unit.

The interfitting engagement of these stepped-bridgesidewall assemblies permits relative axial movement of the two assemblies. This allows the inner sidewalls of each unit pair to be urged into close, sliding engagement with the ends of the central, hub-type piston support members. Escaping piston chamber pressure is conducted into the spaces between the inner and outer sidewalls of each cooperating dual-sidewall unit at each end of the vane piston chamber to overcome the piston chamber pressures urging the sidewalls apart, away from such engagement with the ends of the hub-type support members. This construction permits pressures, developed within the chambers that force the sidewalls apart, away from contact with the central hub-type piston support members, to leak into the closed area between the inner and outer sidewalls of each unit, until pressure builds up sufficiently to urge the inner sidewall toward re-engagement with the ends of the central, hub-type piston support members. A self-regulating seal is thus created, since escaping pressurized gas operates to increase the force tending to seal the piston chamber against this escape; as the sealing action retards the flow of escaping gas, the sealing force instantly and simultaneously diminishes until escaping pressure and sealing force are balanced. Leakage from the annular piston chamber is thus prevented by use of minimum sealing force, thus minimizing sealing friction losses over the zones of sliding engagement between the inner sidewalls and the adjacent ends of the central, hub-type piston support members.

The outer sidewall of one of the pairs of dual-sidewall units may be omitted, so long as the inner piston-engaging sidewall at that end of the piston chamber is firmly joined to the outer sidewall of a dualsidewall unit at the opposite end. The expanding separation of the adjacent sidewalls of this dual unit caused by escaping pressurized gas serves to seal both ends of the piston chamber in the same self-regulating manner described, with minimized sealing force and friction losses, whether dual-sidewall units are utilized at one or both ends of the piston chamber.

Utilizing a single support member to form the entire sidewall of the vane piston chamber, extending radially from its inner periphery to its outer periphery, also serves to eliminate annular gaps, slits or spaces between radially arrayed successive sidewall members which require independent sealing to contain chamber pressures against leakage. Close sliding engagement and resiliently biased sealing rings interposed between the outer peripheries of these inner sidewalls and the outer shell of the casing enclosing the annular vane piston chamber further minimize leakage at the outer peripheries of the pistons.

In addition, toothed, ring-shaped sealing members interfitting with toothed outer flanges on the inner, piston-engaging sidewall members are employed to reduce or eliminate the escape of pressurized gas from one sector-shaped portion of the vane piston chamber past the end faces of a vane piston into the next sector-shaped portion of the vane piston chamber. When pressure leakage is minimized or eliminated in this manner by the sealing assemblies ofthe invention, maximum effectiveness of the pumping or compressing action of these vane piston devices is achieved.

Accordingly, a principal object of the present invention is to provide rotary vane piston devices incorporating pressure sealing sub-assemblies reducing or eliminating the escape of pressurized gas from the sector-shaped portions of annular piston chambers.

Another object of the invention is to provide such rotary vane piston deviceswherein the annular vane piston chambers have each of their axial ends bounded by a unitary sidewall formed by a vane piston support member assembly extending radially across the entire radial width of each chamber end.

Another object of the invention is to provide such rotary vane piston devices in which at least one of the radially extending unitary sidewalls enclosing each axial end of the annular vane piston chamber is integrally connected to an associated outer sidewall member axially spaced adjacent to and beyond the opposite end unitary sidewall member, with conduits being provided to conduct escaping pressurized gas from the annular vane piston chamber into annular disk-shaped spaces between the inner and outer sidewalls, to hold the inner sidewalls in effective, self-compensated sealing position without undue friction, regardless of varying pressures within the annular chamber.

A further object of the invention is to provide rotary vane piston devices incorporating annular piston chambers having sidewall members in sliding engagement with the axial ends of rotary vane pistons mounted for rotational movement therein, incorporating radially outward projecting toothed flanges encircling the outer sidewall periphery adjacent to the vane pistons and separating the vane piston chamber from a first sealing ring groove formed in the outward facing periphery of the inner sidewall member, with the toothed flanges engaging a mating toothed split sealing ring mounted in the first groove having tooth projections extending axially toward the vane piston chamber and interfitting between the corresponding tooth projections extending radially outward from the toothed flange, isolating each sector-shaped portion of the vane piston chamber from adjacent sector-shaped portions thereof.

Other and more specific objects will be apparent from the features, elements, combinations and operating procedures disclosed in the following detailed description and shown in the drawings.

THE DRAWINGS FIG. 1 is an axial cross-sectional side elevation view of a rotary vane piston device incorporating the principles of this invention;

FIG. 2 is a transverse cross-sectional end elevation view taken along the plane 22 shown in FIG. I;

FIG. 3 is a fragmentary enlarged cross-sectional side elevation view of the outer peripheral portions of the adjacent vane piston end and piston chamber sidewall assembly illustrated in FIGS. 1 and 2, taken along the plane 3-3 shown in FIG. 2;

FIG. 4 is an exploded fragmentary enlarged perspective view of the outer peripheral portion of a piston chamber sidewall member, showing the toothed sealing ring and toothed flange assembly thereon;

FIG. 4A is a greatly enlarged fragmentary end elevation view of the same cooperating toothed ring and toothed flange, taken along the plane 22 shown in FIG. 1;

FIG. 4B is an enlarged fragmentary perspective view and FIG. 4C is a greatly enlarged fragmentary end elevation view partly in cross-section, both showing toothed sealing ring sectors incorporated in a modified embodiment of the device;

FIG. 5 is a fragmentary top developed plan view of the peripheral rim of the vane piston and adjoining sidewall assembly illustrated in FIGS. 3 and 4, shown partially in crosssection, and developed from the curved plane 5-5 of FIG. 2;

FIG. 6 is a fragmentary exploded view of a portion of the assembled inner and outer dual sidewall unit positioned at the righthand end of the vane piston chamber in FIG. 1, showing the retaining ring assembly and manner of installation thereon;

FIGS. 7 and 8 are similar cross-sectional views taken along angularly offset radial planes 77 and 8-8 shown in FIG. 6 and illustrating the interfitting block assembly employed for securing the retaining ring to the outer sidewall member;

FIG. 9 is a greatly-enlarged fragmentary axial cross-sectional side elevation view, showing in detail a portion of the rotary vane piston device illustrated in FIG. 1; and

FIG. 10 is an exploded perspective view, partially cut away in cross-section, showing the parts assembled to form an outer sidewall juxtaposed to a unitary inner sidewall which is assembled and anchored to a second outer sidewall at the opposite axial end of the vane piston chamber.

GENERAL DESCRIPTION FIG. 1 shows an axial cross-sectional view of a compressed gas motor or pump incorporating the principles of the present invention. In this figure, motor 20 may be employed as a compressed air motor or as an air pump, useful with either compressed air or other compressed gasses.

The motor20 is provided with an outer casing 21 formed as a dual-walled shell, having three internal cavities 22 and 47A and 48A which are preferably employed as exhaust and intake passages. The cylindrical casing shell 21 encloses a vane piston chamber 23 having the shape of a right circular cylinder, bounded about its periphery by the interior housing wall 24 of casing 21.

The casing 21 is provided with a closed end shown at the right hand side of FIG. 1. At this end of the chamber 23, the casing 21 is provided with heavy-duty rolling bearings, such as the ball bearing 26 and the roller bearing 27, whose outer races are anchored within suitable bearing grooves formed in the righthand end of housing 21. The inner races of bearings 26 and 27 are co-axial with chamber 23, and support a rotatable output shaft 28 provided with an enlarged counterweight 29. Shaft 28 includes an offset crank pin portion 31 which may be formed integrally with, or may be joined by assembling with, a drive shaft portion 32 extending axially and concentrically along the central axis of the casing within the piston chamber 23, to protrude outward from the open end thereof at the lefthand side of FIG. 1. Drive shaft portion 32 is there shown to terminate in a stud shaft 34 rotatably mounted within heavy duty bearings 36, which are firmly anchored within a housing end plate 37 secured by bolts or other means to the open end of casing 21, to enclose the vane piston chamber 23 therein.

Rotatably mounted upon crank pin portion 31 by way of roller or needle bearings 38 is a combined captive connecting member and timing pinion 39 whose teeth are engaged with ring gear teeth 41 formed in an annular control sleeve 42, which is mounted for angular pivoting movement concentric with the axis of casing 21 in heavy duty bearing 43. Control sleeve 42 is pivotally secured by such means as cross head bearings 44 to double-ended pistons 45, mounted for sliding movement within cylinders 47 and 48, shown at the upper and lower righthand portions of FIG. 1. Cylinders 47 and 48 respectively communicate with pressure passages 47a and 48a, which are respectively shown at the upper left and upper right portions of FIG. 2, forming therewith alternative pressure inlet or outlet port passageways through which compressed gas is alternatively introduced into or allowed to escape from piston chamber 23, to produce either counterclockwise or clockwise rotation of output shaft 28 in the compressed gas motor embodiment of the invention. The pressure intake ports through which pressure is alternatively introduced from the passageways 47 and 48 into piston chamber 23 are not shown in the drawings, comparable embodiments being fully described in location, operation and cooperation with the angular control ring gear formed in control sleeve 42 in my US. Pat. No. 3,544,242.

That patent also describes the details of construction and operation of floating connecting members 49 encircling drive shaft portion 32 of the crankshaft at both ends of the piston chamber 23, and also the construction and operation of my captive connecting members such as member 51 rotatably mounted on a heavy duty ball bearing 52 encircling an eccentrically offset drum portion 53 of the drive shaft portion 32 of the crankshaft assembly, shown just to the left of piston chamber 23 at the left side of FIG. I.

PRESSURE SEALING SUB-ASSEMBLIES The transverse cross-sectional view of FIG. 2 demonstrates I four sets of vane pistons 61, 62, 63 and 64, successively interposed and arrayed angularly around the annular piston chamber 23. The angular acceleration and deceleration of the vane pistons are governed by the floating and captive connecting members joining these vane pistons by way of support members to the crankshaft 28-32.

The support members are clearly shown in the axial crosssectional elevation view of FIG. 1. Support member 71 is integrally joined to all of the vane pistons 61 and support member is integrally joined to all of the vane pistons 63, as indicated in the upper portion of FIG. 1. Both of these support members 71 and 73 are hub-typed" support members having central hub sleeves 71A and 73A telescopingly and slidingly mounted on the drive shaft portion 32 of the crankshaft assembly, for relative angular movement thereon. The left hubtype support member 71 is connected by way of a crosshead bearing slide 718 to the captive connecting member 51 at the lefthand side of FIG. 1, and by similar crosshead bearing slides 71C to the two floating connecting members 49 at the lefthand and righthand side of FIG. 1. The righthand crosshead bearing slide 71C is connected to sleeve 71A by a stepped-bridge member 71D overlying the supporting sleeve 73A, as shown at the right center portion of FIG. 1.

Sleeve 73A is provided with a similar stepped bridge portion 73D overlying sleeve 71A, connecting the support member 73 to the left floating connecting member 49 at an angular position not shown in FIG. 1. In this manner, the overlying stepped bridge members and the opposite underlying flanges interfitting therewith provide end connections for these support members 71 and 73, operatively joining them to both of the floating connecting members 49 and to captive connecting member 51.

These interfitting stepped bridge members are provided with sufficient angular leeway to permit angular acceleration and deceleration movement of the vane pistons in chamber 23, controlled by the floating connecting members 49 and the captive connecting members 39 and 51. This leeway is shown in the central portion of FIG. 2, where the central shaft 32 is shown surrounded by the end of sleeve 73A, whose projecting stepped bridge fingers 73D are shown in cross-section extending toward the viewer, interspaced between intertitting stepped bridge fingers 71D angularly positioned therebetween, leaving ample angular space for angular acceleration and deceleration movement between the stepped bridge fingers 71D and 73D.

The integral connection of hub-type support member 73 with vane pistons 63 is clearly shown in FIG. 2, and the corresponding integral connection of hub-type support member 71 with pistons 61 is shown in FIG. 1. The vane pistons 62 and 64 of the other two sets of pistons are positioned for sliding angular movement around the hub-type support members 71 and 73, with resilient sealing bars 66 positioned in sealing grooves formed in these vane pistons and extending in sliding sealing engagement with the outer peripheries of hub-type support members 71 and 73. As shown in FIGS. 3 and 5, similar end sealing bars 67 are positioned in sealing grooves recessed in the end surfaces of the vane pistons, for sliding engagement with sidewalls 72 and 74; and rim sealing bars 68 are positioned in grooves recessed in the radially outermost rim surfaces of the vane pistons, for sliding engagement with housing wall 24. Bars 67 are preferably provided with stepped ends for dovetailed overlapping engagement with the adjacent ends of bars 66 and 68.

PISTON CHAMBER SIDEWALL UNITS The hub-type support members 71 and 73 provide the radially innermost peripheral walls of the annular piston chamber 23, and the peripheral housing wall 24 of casing 21 surrounding the chamber 23 provides the radially outermost peripheral wall for the chamber.

- As shown in FIG. 1, the left and right ends of piston chamber 23 are each respectively closed by a unitary sidewall 72 or 74 extending over the entire radial width of each end of the chamber. At the left end, sidewall 72 is integrally formed with or bolted to each of the vane pistons 62, as shown in the lower central portion of FIG. 1, forming a side support member for all of these pistons 62. A similar right sidewall 74 is integrally formed with or bolted to the vane pistons 64, spanning the entire radial end of the chamber 23 as indicated in FIG. 1. The right sidewall 74 is shown in the detailed, cutaway exploded view of FIG. 10, where its interfitting relationships with associated parts are illustrated in detail.

The construction and operation of each of the chamber sidewalls 72 and 74 is substantially identical, and these will be described with particular reference to FIGS. 1 and 10. As shown in these drawings, right sidewall 74 is provided with a flat, washer-shaped or disk-shaped portion 75 comprising the end wall of the chamber 23. A central aperture in this washer disk 75 is formed by an inner flange 76 protruding from the chamber side of the washer disk 75 and underlying the rim of the hub-type support member 73 in the assembled device shown in FIG. 1. The outer peripheral surface of inner flange 76 is provided with two sealing ring grooves 77 in which split, resilient sealing rings are positioned for sliding engagement between the outer periphery of inner flange 76 and the facing surface of hub-type support member 73, acting like piston rings in conventional internal combustion engines to minimize leakage of compressed gas between the two members 73 and 76. I As shown in FIG. 10, the left face of this right sidewall 74 facing the vane pistons in chamber 23 is smooth and flat for sliding sealing engagement with resilient sealing bars 67, which are seated in sealing slots in the end faces of the vane pistons for sliding sealing engagement with this left surface of right sidewall 74.

At the outer periphery of sidewall 74, an outer flange 78 extends axially outward away from chamber 23 to the right in FIGS. 1, 3, 4, 6, 7, 8 and 10. As shown in these drawings, a first ring groove 79 is formed in the outer peripheral surface of outer flange 78, and this groove 79 is spaced axially away from the facing end surfaces of all of the vane pistons only by the width of a toothed flange 81, from which gear teeth 80 protrude radially outward. As shown in FIGS. 3, 4 and 10, three additional ring grooves 82 are recessed in the outer periphery of outer flange 78, and they are spaced apart by intervening lands whose outer diameter is dimensioned for noninterfering telescoping insertion and for free rotation of the sidewall 74 within peripheral housing wall 24 of the casing 21.

The space between the outer diameter of these lands and the facing surface of peripheral housing wall 24 may amount to a few thousandths of an inch. To prevent the escape of compressed gas between flange 78 and wall 24, resilient split sealing rings corresponding to the piston rings of conventional internal combustion engines are mounted in the grooves 82, and the natural resilience of these rings urges them outwardly toward wall 24, substantially blocking the escape of compressed gas.

To prevent the escape of compressed gas around the topmost corners of any vane piston across the top of the teeth 80 on flange 81, a split sealing ring 83 seated in groove 79 is provided with interfitting teeth or projections 86 protruding laterally from groove 79 between teeth 80 toward the'end walls of the vane pistons in chamber 23. Installation of this ring 83 is achieved by insertion of a split spacer ring 87 in abutting engagement with toothed sealing ring 83, best shown in FIG. 4, extending substantially around the entire periphery of the sidewall 74. The ring 83 is formed as a split ring or an encircling group of two or three ring sectors for insertion within the first ring groove 79. Resilient ring or ring sectors 83 are dimensioned for outwardly flexed resilient sliding engagement with housing wall 24. This toothed ring 83 in the first sealing ring groove 79 extends substantially around the entire encircling periphery of each outer corner of combustion chamber 23.

As indicated in FIGS. 3 and 4, groove 79 is substantially twice as wide axially as toothed flange 81. The split toothed sealing ring 83 is provided with a ring flange 84 resembling a conventional thin sealing ring like those in the additional sealing ring grooves 82. Protruding toward the annular chamber 23 from the side face of ring flange 84 are a plurality of tooth projections 86 formed in the shape of ring gear teeth having gear tooth spaces between them for insertion between protruding gear teeth 80 on flange 81 for intermeshing engagement therewith. The root circle or base diameter of the teeth 80 formed in the periphery of flange 81 is greater than the inside diameter of groove 79, providing a smooth unbroken rear face of flange 81 facing the base of the first ring groove 79 for facing engagement with the corresponding smooth juxtaposed face of the ring flange 84 of toothed sealing ring 83. The outer diameter or maximum dimension ofthe teeth formed in flange 81 is selected to be less than the internal diameter of peripheral housing wall 24. If desired, this dimension may be somewhat less than that of the lands spaced between the additional ring grooves 82. As indicated in FIG. 4A, engagement of the toothed projections 86 of toothed sealing ring 83 intermeshed between the teeth 80 formed in toothed flange 81 permits slight angular shifting of the outwardly resiliently biased ring 83 to a contacting position bringing the intermeshing teeth 80 and 86 into contacting engage- -ment. The corresponding spaces between the intermeshing teeth form small Z-shaped cavities bounded by ring 83, the root diameter of the teeth 80 formed in rim 81, housing wall 24 and the facing surfaces of the intermeshing teeth. These 2- shaped chambers face the annular piston chamber 23, and they are sealed off successively by vane pistons moving past the aligned exposed surfaces of projections 86 and flange 81. As indicated in the developed cross-sectional plan view of FIG. 5, these intermeshing toothed structures fill the space between sidewall 74, peripheral housing wall 24 and the outer corners of the vane pistons. Accordingly, compressed gas is blocked from escaping past these outer piston corners from one sector-shaped portion of the chamber 23 into an adjacent sector-shaped portion.

First sealing ring groove 79 is preferably slightly more than double the width of ring flange 84 of toothed sealing ring 83, permitting the ring 83 to be resiliently flexed to its outwardly sprung installation diameter for insertion over toothed flange 81 into this groove 79 behind the teeth of flange 81. The split sealing ring 83 may then be allowed to resume its normal diameter bringing its tooth projections 86 into alignment for interfitting engagement between the teeth 80 of flange 81, and

thus aligning ring 83 for axial sidewise movement toward chamber 23. This brings the intermeshing teeth 86 into engagement with the teeth on ring 83-, with the chamber faces of teeth 80 and 86 being aligned substantially in the same sidewall plane, as indicated in FIGS. 3, 7 and 8.

With the intermeshing teeth engaged in this manner, a split spacer ring 87 may be resiliently defonned outwardly for insertion into the space behind sealing ring 83 in first ring groove 79, blocking the withdrawal of tooth projections 86 from between the teeth 80 formed in toothed flange 81, and thus positioning the assembled structure for reliable sealing engagement with the sealing bars 67 in end faces of all vane pistons moving angularly in the chamber 23.

The presence of this additional split spacer ring 87 behind the sealing ring 83 maintains the ring flange 84 in close juxtaposed engagement with the rear side of toothed flange 81, minimizing or substantially eliminating clearance between the face of ring 83 and the juxtaposed teeth 80 formed in flange 81. Accordingly the escape of compressed gas behind the teeth 80 of flange 81 is substantially eliminated by these sealing assemblies.

SPRING PLUNGER BIASED TOOTHED SEALING RINGS As indicated in FIG. 4A, the relative rotation of side-wall 74 within stator housing 24 results in friction drag forces imposed by housing 24 upon toothed sealing ring 83, causing its protruding teeth 86 to bear against the forward faces of the intermeshing teeth 80 formed in the flange 81 of the sidewall 74, which thus pushes" sealing ring 83 ahead of it around the vane piston chamber, thereby producing the Z-shaped cavities between teeth 80 and 86 shown in FIG. 4A. Toothed sealing ring 83 is normally oversize and resiliently self-biased outward, and it is installed compressed within its groove 79 to provide automatic self-biasing force urging it toward housing 24. This toothed sealing ring 83 is a split sealing ring extending for nearly 360 around the periphery of the device. Careful manipulation is often required to expand ring 83 sufficiently for insertion and to engage its teeth 86 with the teeth 80 of sidewall 74 successively around the periphery of the sidewall rim. In operation, the resilient inward deformation of sealing ring 83 by its compression inside housing 24 may sometimes result in uneven outward sealing force, providing better sealing at certain portions of the periphery of the device than are achieved at other portions. When shorter sectors of sealing ring 83 are employed, such as I80 sectors, the self-biasing force produced by the inward resilient deformation of these sectors produces sealing force at their ends much greater than the sealing force produced at the middle of such sectors.

An alternative toothed sealing ring construction tending to overcome these problems to a significant extent is shown in FIGS. 4B and 4C, and is adapted to be used with sector portions 102 of toothed sealing rings extending between adjacent pistons of a piston set around the periphery of either inner sidewall unit, such as sidewall 74 shown in FIG. 4B. Each toothed ring sector 102 extends around the sidewall rim between the adjacent pistons of the same set subtending an arc somewhat less than 90 with a four-piston set, for example. In FIG. 4B, the piston set 64 includes two pistons protruding inward from sidewall 74, and two sealing ring sectors 102 extend around the periphery of sidewall 74 between the central planes of these two pistons 64 subtending only slightly less than l80 each.

The protruding teeth 86 ofthese sector sealing rings 102 extend axially between the engaging teeth 80 of rim 81 of the inner sidewall 74 as shown in the lower portion of FIG. 4B and the left side of FIG. 4C. At the ends of the sector sealing rings 102, the last few teeth 86 are omitted to allow the ring sector end to be received in an untoothed portion of slot 79 extending behind piston 64 at the point where it is anchored to sidewall 74 as shown in FIG. 4B.

The extreme inner corners of sealing ring sectors 102 are preferably chamfered at about 45. for sliding engagement with the double beveled end of a plunger 103 resiliently biased in a radially outward direction projecting from a radial plunger recess 104 into groove 79. Plunger 103 is biased by such means as a compressed helical coil spring 106, compressibly sandwiched between plunger 103 and the blind end of plunger recess 104, as shown in FIG. 4C. The adjacent ends of two sector sealing rings 102 engage oppositely sloping diagonally chamfered camming surfaces formed on the inner end corners of plunger 103, and the force supplied by compressed spring 106 urging plunger103 radially outward produces sliding displacement of the toothed sealing ring sectors 102, urging them radially outward and apart in groove 79. Outward motion of the sealing ring sectors 102 is arrested by their engagement with the inner surface of housing 24 and the force of spring 106 causing their peripheral separation assures relatively even sealing force distributed around the periphery of the ring sectors 102 urging them radially into contact with the housing 24 uniformly about their entire outer peripheries.

Installation of a sealing ring sector 102 is illustrated in FIG. 413, where separating forces applied by the user draw the free ends of sector I02 apart, allowing it to slip freely into groove 79 with all of its axially protruding teeth 86 interfltting between the teeth 80 formed in rim 81 of sidewall 74 as sealing ring sectors 102 are inserted into sealing ring slot 79. The adjacent ends of sectors 102 are spaced apart sufficiently to permit resilient flexing deformation of the sectors 102, assuring their uniform radial sealing action around the entire periphery of sidewall 74.

The natural resilience of the sealing ring sectors 102 is utilized by dimensioning and shaping these sectors so that their unstressed diameter is slightly less than the diameter of slot 79, thus tending to hold them in interfltting engagement therein. The natural resilient restoring force of the sealing ring sectors 102 is counteracted by the radial biasing force supplied by springs I06 and plungers I03. Springs 106 also compensate for peripheral wear on the outer rim of sealing ring sector 102 by producing outward camming force continuing to impel sealing ring 102 radially outward around its entire periphery as this periphery slowly wears away during the running-in operation of the device. In these assemblies, each of the chamber sidewalls 72 and 74 provides peripheral sealing for the engaging faces of all vane pistons, excepting only those anchored to and supported by the sidewall itself, such as the pistons 64 cantilevered from sidewall 74, as shown in FIG. 4B. These sealing ring sector assemblies thus produce uniform peripheral sealing action around the outer corners of all the vane pistons, assuring effective isolation of each successive sector of the vane piston chamber 23.

A somewhat comparable sealing proposal appears in Tschudi U.S. Pat. No. 3,38l,669, incorporating a serrated or toothed flange 35 interposed on a piston support member between a pair of sealing rings 34 and a piston 18a. The text of this Tschudi patent suggests that sealing rings 34 may be provided with protrusions engaging the depressions in the flange serrations 35 to obtain a pressure seal. However, this Tschudi patent fails to suggest the form such protrusions should take, and only a small sector of the support member beside its own piston is provided with such serrations in these Tschudi devices. Tschudis support member thus provides no sealing action for any piston carried by another support member.

By contrast, sealing rings 83 or 102 of the present invention and the teeth 80 formed in flange 81 both extend around the entire exposed periphery of the vane piston chamber sidewall, serving to seal the cylindrical chamber with unusual effectiveness against leakage of pressurized gas past each of the vane pistons into the chamber sector beyond the piston. No such sealing capability is possible with the Tschudi device.

DUAL SIDEWALL SEALING OPERATION The component parts and their interfltting engagement with the assembly of the stepped bridge support member joining the right inner sidewall 74 to the left outer sidewall 88 are clearly shown in the assembled view of FIG. I and the exploded view of FIG. 10. The right inner sidewall 74 and the left outer sidewall 88 are joined together in an anchored unitary assembly by a stepped bridge member 89. As shown in the central portion of FIG. 10 and in cross-section in FIG. 1, this stepped bridge member 89 is provided with sector cutouts accommodating, in back-to-back juxtaposition, a corresponding, reversely steppedbridge member 91 interfitting therethrough and joining the left inner sidewall 72 to a right outer sidewall member 92. In the exploded perspective view of FIG. 10, the left inner sidewall 72 and the reversely stepped bridge member 91 are both omitted for clarity, and the right outer sidewall 92 forming a duplicate of the left outer sidewall 88 is shown at the righthand end of FIG. 10.

All of these parts in their assembled positions are shown in the central portion of FIG. 1. As there shown, outer sidewall members 88 and 92 are provided with outwardly extending axial flanges 93 and 94. Left outer sidewall member 88 thus terminates radially in an axially extending flange 93 fitting inside a corresponding axial flange 95 forming the outer periphery of left inner sidewall member 72. The outer rim of flange 93 is provided with ring grooves incorporating sealing rings acting like piston rings in conventional internal combustion engines and resiliently self-biased outwardly toward the inside rim of flange 95. In a similar manner, sealing ring grooves are provided encircling the outer periphery of flange 95 accommodating sealing rings resiliently self-biased radially outward toward the peripheral housing wall 24.

Correspondingly, the right dual sidewall unit at the right end of the vane piston chamber comprises inner sidewall unit 74 and outer sidewall unit 92 shown disassembled in the exploded perspective view of FIG. 10. An axially extending outer flange 94 encircles the radial periphery of outer sidewall member 92 nesting inside the internal diameter of a similar axially extending flange 78 forming the outer periphery of the inner sidewall unit 74, and shown in greater detail in FIGS. 6, 7 and 8.

The dual sidewall unit 74-92 at the right end of the vane piston chamber is shown in the central portion of FIG. 1, where the space between these inner and outer sidewall members is seen to be an axially thin, disk-shaped space 99, outwardly terminated by flange 78 and inwardly terminated by a flexible sealing ring 96, which is a thin dual-leaf spring having a V-shaped cross-section, and which is preferably stamped of thin resilient metal such as spring steel and is capable of axial flexing to bring the leaves or sides of the V closer together.

As indicated in FIG. 9, showing a greatly enlarged view of the lower portion of the V-shaped sealing spring strip 96, this strip is held captive in a pair of facing grooves, a recessed groove 97 encircling the periphery of inner wall 74 near its innermost edge, and a juxtaposed recessed groove 98 encircling the facing inner surface of the outer sidewall 92. The space between the sidewalls 74 and 92 may thus be described as a thin, disk-shaped cavity 99, and a corresponding cavity 99 is shown at the left end of FIG. 1 between the left inner sidewall 72 and the left outer sidewall 88.

sealing sleeve 100 nested inside members 71 and 73 and bearing against their inner peripheries, as shown in the central portion of FIG. 1. Accordingly, the path of least resistance for pressurized gas tending to escape from the compression sectors of the vane piston chamber is provided by a plurality of diagonal vent passages 101 connecting the inner peripheral portion of the disk shaped cavities 99 with the inner, piston engaging face of the inner sidewalls 72 and 74 at points spaced radially inward from the piston chamber and normally covered by the abutting juxtaposed end surface of hub-type support members 71 and 73. The vents 101 formed around the inner periphery of the right inner sidewall member 74 are clearly shown in the exploded perspective view of H010,

where the lower cutaway cross-section portion of right inner sidewall 74 reveals one of the vent passages 101. In the greatly enlarged cross-sectional view of FIG. 9, this same vent 101 is again shown in cross-section, communicating from the sealing ring groove 77 region of the stepped flange 76 protruding axially toward the piston chamber at the inner periphery of right inner sidewall 74, and extending diagonally outward past the V-shaped sealing spring 96 into the interior of disk-shaped cavity 99. The corresponding vents 101 formed in the left inner sidewall member 72 at the left end of the vane piston chamber are clearly shown in FIG. 1.

Escaping gas passing radially inward between hub-type support member 73 and adjacent inner sidewall 74 in the greatly enlarged fragmentary cross-sectional view of FIG. 9 follows the path of the arrows there shown between support member 73 and sidewall 74 into diagonal vent passages 101 and thence into disk shaped cavity 99. Admission of escaping pressurized gas into the disk-shaped cavity 99 produces a self-balancing sealing operation, becauseescaping gases leaking between members 73 and 74 are substantially all contained within cavity 99. The V-shaped sealing spring 96 has its leaves or sides bowed apart by the increasing pressure in cavity 99, providing an improved seal within the recessed grooves 97 and 98, and the pressure within cavity 99 is also contained by the sealing rings seated in flange 94 of outer sidewall member 92 bearing against the inner periphery of flange 78 on inner sidewall 74.

The axially movable outer end wall member 92 may be provided with an axially extending flange slidingly and ringsealably engageable inside the adjacent rim of hub-type support member 73. With this construction, the outer end wall member itself encloses the leakage spaces between the as sociated inner sidewall support member 74 and its abutting hub-type support member 73, forming therebetween a gas conducting vent channel passageway replacing diagonal channels 101, with the ring-sealed flanges of members 73 and 92 replacing the V-shaped spring 96 sealing the internal periphery of sealing pressure chamber 99.

Accordingly, the trapped pressurized gas tends to force apart the two facing sidewall units 74 and 92. The resulting pressure upon inner sidewall 74 urges it toward the right ends of the vane pistons in the piston chamber, and also toward the facing right end of the inner hub-type support member 73, thereby reducing the admission of pressurized gas between members 73 and 74 into passages 101 and thence into cavity 99.

At the same time the pressure within cavity 99 tends to urge outer sidewall 92 away from the piston chamber, drawing with it the opposite inner sidewall 72 at the left end of the piston chamber into tighter sealing engagement with the left ends of the vane pistons therein and with the left end ofthe inner hubtype support member 71, reducing the escape of pressurized gas between inner sidewall 72 and hub-type support member 71.

Accordingly, increasing pressure in cavity 99 reduces the space available between the inner sidewall and the hub type support members through which pressurized gas can escape into cavity 99, thus producing a self defeating sealing action and causing the sealing pressure force to achieve an equilibrium condition at which the volume of pressurized gas escaping through vents 101 is just sufficient to maintain the sealing pressure. When higher pressures occur in the vane piston chamber, causing an increase in the escaping volume, the resulting increasing pressure in cavity 99 creates greater axial resultant forces tending to separate sidewalls 74 and 92, producing inward movement of both inner sidewalls 72 and 74, thereby again reducing the volume of escaping gas and thus balancing the sealing pressure with the escaping gas pressure trapped in cavity 99. As a result, sealing friction is minimized while the escape of pressurized gas is reduced to a minimum.

The outward movement of right outer sidewall 92 away from the v'ane pistons caused by the pressure escaping from the piston chamber into the cavity 99 is transmitted through stepped bridge member 91 to draw left inner sidewall 72 toward the vane pistons. When only one dual sidewall unit is incorporated in the devices of this invention, such as the dual sidewall unit 74-92 at the righthand side of the vane piston chamber in FIG. 1, the entire self-balancing sealing operation is performed by the cavity 99 between the inner sidewall 74 and the outer sidewall 92 comprising this dual sidewall unit, with inner sidewall 74 being urged by the sealing pressure against the right hand end faces of all vane pistons and with the movement of outer sidewall 92 toward the right caused by the pressure in the cavity 99 serving to draw inner sidewall 72 at the left end of the piston chamber into sealing engagement with the left end faces of all of the vane pistons in the chamber. In this embodiment of this device, the vents 101 in the left inner sidewall 72 may be omitted since only the diskshaped cavity 99 between the right dual sidewall 74 and 92 is operative to provide sealing force.

In the embodiment shown in FIG. 1, incorporating dual sidewall units both at the left end and at the right end of the vane piston chamber, escaping pressurized gas enters either of the cavities 99 at either end of the vane piston chamber, serving to seal both ends of the chamber with great effectiveness, since interfltting stepped bridge members 89 and 91 serve to transmit sealing force from each cavity 99 to the opposite inner sidewall 72 or 74, whether or not a sealing force is developed in the other cavity 99 directly associated with that sidewall.

In view of the substantial operating pressure differentials existing between the high pressures developed within the vane piston chamber and ambient external atmospheric pressure, some slight measure of pressure leakage from the piston chamber past the sealing rings is normally unavoidable. The dual-walled sealing assemblies of this invention take advantage of this minor leakage pressure to provide a self-biasing and self-regulating sealing force applied by the end walls of the piston chamber against the end faces of the pistons, thus serving to minimize the pressure leakage between sectors of the vane piston chamber having different pressures, such as the power" sector containing the compressed or ignited mixture of fuel and air, whose pressure will be substantially higher than a neighboring chamber sector passing through its exhaust or intake" stage of operation. In this fashion, normal escaping leakage gases are employed with great effectiveness to produce the sealing force utilized to isolate the separate sectors of the vane piston chamber to the maximum possible extent, and the extreme corner peripheries of the vane pistons are simultaneously sealed with high effectiveness by the toothed sealing rings 83 or 102 cooperating with teeth formed in flanges 81 of both inner sidewalls 72 and 74, further assuring the isolation ofthe different sectors ofthe vane piston chamber between the angularly accelerating and decelerating vane pistons.

TAPERED SEGMENT LOCKING RINGS A six-part ring assembly comprised of separate sector segments slidingly engageable by axial relative movement to secure the stepped bridge member 89 to the inner periphery of the left outer sidewall member 88 is shown in the left portion of the exploded view of FIG. 10. The sector segments of this locking ring assembly somewhat resemble interfitting splines, but these sector segments are not all straight." Instead, a helical bounding surface of extremely steep pitch extends along one edge of a first sector segment and cooperates with a mating helical bounding surface of the adjacent segment to assure locking engagement of the sector segments in their assembled relationship.

As shown in FIG. 10, the stepped bridge member 89 is provided with a pair of anchoring flanges 112 provided with bores aligned with threaded apertures centrally positioned in the right inner sidewall member 74 to provide secure bolted attachment between stepped bridge member 89 and the inner periphery of inner flange 76 of the sidewall unit 74.

In order to regulate the stability of motor operation when the phonograph is'in a play mode, a damping potentiometer 182 is connected between the servo-control unit and one of the normally open contacts of reversing switch 103. The damping potentiometer is provided for adjusting the gain of the servo-control unit to correct for physical changes (such as increased friction in the turntable bearings because of dirt in the mechanism) in the phonograph mechanism. Access to the damping potentiometer is had through an access hole 183 formed in the back plate of the phonograph housing (see FIG. 3).

The audio portion of the circuitry of the phonograph is illustrated in FIG. 16B. Stereo amplifier 106 preferably is a transistorized, modularized unit which is connected into the circuitry of the phonograph via a connector 184. Signals from the left and right terminals of stereo cartridge 79 are supplied to the amplifier via a connector 185 for a remote loudspeaker unit 186 (described in detail below) and via volumetone control unit 108. The connector for the remote loudspeaker unit preferably is a 74-inch phone jack incorporating a single-pole double-throw switch 187, having a normally open contact 188 and a normally closed contact 189. The left channel output terminal of the stereo cartridge is connected to the common element of switch 187 and the right channel terminal of the cartridge is connected to contact 189. In the normal condition of the switch, therefore, the left and right channel signals produced by the stereophonic stylus cartridge are mixed prior to introduction of these signals to the volume-tone control. As a result, even through a stereophonic record may be played in the phonograph, the sound producedby loudspeaker 107 is essentially monophonic sound when the remote speaker unit is not is use.

An earphone jack 190' incorporating a single-pole singlethrow switch 191 is connected in parallel with loudspeaker 107, as shown in FIG. 16B. The earphone jack is accessible through the front of the phonograph as shown in FIG. 13. When a conventional earphone plug 192, provided as a part of an earphone assembly 193, is engaged with the earphone jack, switch 191 is opened to effectively disconnect loudspeaker 107 from the amplifier.

Remote loudspeaker unit 186 is provided with a suitable length of three-conductor cable 194 to which is connected a jack 195 configured for cooperation with phone jack 185. The remote loudspeaker unit is provided for reproducing left channel sound derived from stereophonic cartridge 79. When jack 195 is engaged with connector l85, switch 187 is operated to place the switch in a condition whereby no mixing is obtained of the signals derived from the left and right channel terminals of the stylus cartridge. Instead, when the remote speaker unit is in use, the left and right channel signals from the cartridge are applied separately to the respective channels of the amplifier via volume-tone control 108. During stereophonic operation of the phonograph, loudspeaker 107 serves as the right channel loudspeaker, whereas a loudspeaker 196 in the remote speaker unit serves as the left channel speaker. The speaker within phonograph housing 21 is selected as the right channel loudspeaker in view of the practices which have been established as standard in the manufacture of stereophonic records.

It is now standard practice in the phonograph recording industry to record a full audio spectrum in the right channel, i.e., on the right side of a phonograph record groove, and to record only the upper portion of the audio spectrum in the left chan' nel, i.e., left side, of the record groove. In other words, a truly stereophonic effect is maintained only with respect to intermediate and high audio frequencies, but not with respect to bass frequencies. This is done because the human ear is relatively insensitive to the directionality of base sounds, whereas it is highly sensitive to the directionality of treble and midrange sounds.

It is desired that remote speaker unit 186 be provided as a relatively low cost accessory to phonograph 20. Accordingly, the loudspeaker within the phonograph itself is selected as the right channel speaker since this loudspeaker can realistically be more costly than loudspeaker 196, and thus be better suited for reproduction of a full audio spectrum.

Remote speaker unit 186, shown in FIG. 17, has a housing 197 having front-to-back and transverse dimensions substantially equal to the corresponding dimensions of phonograph housing 21 so that it is generally of similar size and shape to housing 21. The remote speaker housing has a top surface 198 defining a grille 199 below whichremote speaker 196 is mounted, the speaker preferably being an oval speaker mounted adjacent one end of the housing. A generally tubular extrusion 200 of low thermal conductivity material, such as vinyl plastic having a coefficient of thermal expansion similar to that of the material from which phonograph records are made, is located in the housing laterally of the loudspeaker and defines an elongate record storage chamber 201 extending between the front and the rear of the housing. The transverse dimension of the chamber is slightly greater than 7 inches. A hinged door 202, extending across the chamber, forms a part of the housing and is secured in closed relation to the housing by a thumbscrew 203. The chamber serves as a storage compartment for a quantity of 7-inch records; earphones and other accessories can be stored between the extrusion and the housing. Because of the nature of the material from which the extrusion is made, the extrusion and any records in chamber 201 expand atthe same rate in response to temperature changes, and any thermally induced warpage of the record is minimized.

A laterally extended hook projection 204 extends from the' front edge of the bottom of housing 197 (see FIG. 18). A leaf spring 205 is riveted to the back of the housing and extends beyond the bottom of the housing into a hook portion 206. The hook projection may be engaged over the front edge of the top plate of the phonograph housing, and the hook portion of spring 205 may be engaged over the rear edge of top plate 22 (see FIG. 18) so that both units can be carried together by means of handle 32. The spring loading of hook 206 maintains the speaker unit in engagement with the phonograph until the two units are intentionally separated.

When stereophonic operation of phonograph 20 is desired, the remote speaker unit is coupled to the phonograph via extension cord 194. Insertion of jack 195 into phone jack 185 separates the right and left channel signals from cartridge 79 and causes these signals to be applied to corresponding channels of amplifier 106.

The amplifier of phonograph 20. may be used, if desired, to drive two remote loudspeakers other than the remote speaker unit described. In such a case, the right channel loudspeaker is provided with a jack suitable for engagement in receptacle 190, and the left channel loudspeaker is provided with a jack suitable for engagement in receptacle 185.

There has been described above a versatile, portable, attitude insensitive record player. The record player may be operated from batteries contained within it, or it can be powered from a volt AC. power source or from an automobile ignition system. Also, either external power source can be used for the purpose of recharging the batteries contained within the phonograph housing. Only a single motor is used for rotating, clamping and rejecting a record inserted into the player. The record drive mechanism features a motor arrangement which is low in mass and mechanical inertia, yet precise control over the rotational rate of the record turntable is assured. Multiple uses are had of many elements of the record player structure so as to provide a simple, rugged and efficient product. 1

While specific arrangements and structures have been described in the foregoing description of a presently preferred embodiment of the invention, this has been by way of example and illustration rather than limitation. Accordingly, the foregoing description is not be regarded as limiting the scope of this invention.

What is claimed is: Y

1. A record player comprising a record turntable having an axis of rotation about which the turntable is rotatable and D. and vent channel means connected to convey leakage gas escaping from the annular chamber into the sealing pressure chamber, tending to separate the endwall and the adjacent sidewall support member.

4. The device defined in claim 3 wherein each of the two sidewall support members is integrally connected to one outer endwall positioned at the opposite end of the annular chamber beyond and in adjacent axial juxtaposition behind the other sidewall support member, forming an axially expansible sealing pressure chamber between each sidewall support member and its adjacent endwall.

5. The device defined in claim 3 wherein each sidewall support member is positioned in sliding abutting juxtaposition at the axially outermost end of a central hub-type support member,

and wherein the vent channel means comprise passageways extending through the sidewall support member and connecting portal ends thereof exposed to the abutting juxtaposed hub-type support member with discharge ends exposed to the sealing pressure chamber, whereby leakage gas escaping from the annular chamber between the sidewall support member and the juxtaposed hub-type support member is conducted into the sealing pressure chamber, urging each of the sidewall support members simultaneously into closer sliding abutting engagement with the end of the hubtype support memberjuxtaposed therewith.

6. The device defined in claim 3 wherein each sidewall support member is positioned in sliding abutting juxtaposition at the axially outermost end of a central hub-type support member, and wherein the outer end wall is axially movable and is provided with an axially extending flange slidingly and sealingly engageable with the adjacent hub-type support member, thereby enclosing a gas conducting vent channel passageway formed between the associated sidewall support member and its abutting hub-type support member, so that gas escaping from the piston chamber as a result of axial separation of the sidewall support members is conducted primarily into the sealing pressure chamber.

7. In an alternately accelerating rotary piston device of the character described, including a stator housing containing an annular chamber and a plurality of sets of angularly spaced vane pistons successively arrayed in the chamber, each set having at least two vanes secured to a support member and all sets having their relative angular positions determined by connecting members interconnecting the support members to a crankshaft wherein the stator housing forms an outermost peripheral bounding wall of the annular chamber, the improvement comprising A. a pair of said piston support members forming sidewall members respectively positioned at each axial end of the annular chamber and extending radially into slidingly sealed engagement with the outermost peripheral bounding stator housing wall;

B. means forming a plurality of sealing ring grooves encircling the periphery of each sidewall support member facing the stator housing wall;

C. a corresponding plurality of sealing rings positioned in the encircling grooves and protruding radially therefrom into sliding sealing engagement with the stator housing wall; D. an axially innermost first sealing ring groove formed in each sidewall support member adjacent to the annular chamber and separated therefrom by a sealing flange hav- "*8 5 crenel apertures formed therein joining the first sealing ring groove with the annular chamber periphery,

angularly spaced about substantially the entire periphery of the sidewall support member not occupied by pistons supported thereby;

E. and a first sealing ring positioned in the first sealing ring groove and provided with projections aligned with and extending axially through the crenel a ertures into angular sliding sealing engagement with t e juxtaposed end walls of the pistons not supported by the sidewall member in which the crenel apertures are formed;

whereby gas pressures occurring in adjacent annular chamber sectors on opposite sides of a vane piston are confined between each crenel aperture and its engaging projection, maintaining each chamber sector in pressure sealed integrity substantially isolated from the adjacent chamber sectors.

8. The device defined in claim 7 wherein the crenel apertures are formed as radially diverging apertures substantially trapezoidal in cross-section,

and the projections on the first sealing ring extending therethrough are formed with correspondingly shaped trapezoidal cross-sections.

9. The device defined in claim 7 wherein the crenel apertures are formed as radially diverging apertures separated by gear tooth-shaped merlons extending radially outward therebetween,

and the first sealing ring projections extending therethrough are formed with gear-tooth shaped cross-sections for intermeshed engagement with the merlons.

10. The device defined in claim 7 wherein the first sealing ring is a divided ring having a circumference less than a complete circle.

11. The device defined in claim 7 wherein the first sealing ring comprises a plurality of angular sectors arrayed end-toend in the first sealing ring groove.

12. The device defined in claim 11 wherein the sealing ring sectors each extend between the midpoints of adjacent pistons of the vane piston set secured to the sidewall support member carrying the sealing ring sectors.

13. The device defined in claim 11 wherein the radius of curvature ofthe sectors is less than that of the bounding stator housing wall, and wherein the ends of the sectors are resiliently biased radially outward into engagement therewith.

14. The device defined in claim 13, further including compression springs each positioned in a peripheral recess formed in the sidewall support member underlying the adjacent ends of two ring sectors and resiliently compressed therein to impose radial outward force urging the ring sector ends outwardly toward the outermost bounding chamber housing wall.

15. The device defined in claim 14 wherein each peripheral recess is angularly positioned at themidpoint of a vane piston secured to the sidewall support member carrying the sealing ring sectors.

Patent No. 3,658, m7 Dated 1 43101125, 1972 Inventor s) Charles Bancroft It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Cancel columns lflj and 1M and substitute the attached pages p As shown in FIGURE 10, a pair of sector segments 113 each subtending approximately 60 degrees of the periphery of stepped bridge member 89 protrude therefrom in an axial direction toward the outer sidewall member 88 at the opposite end of the vane piston chamber 23.

Flanges 113, as viewed from the left or sidewall 88 end of the device, are bounded along their clockwise edges by an axial FORM pomso (1069) USCOMM-DC 60376-P69 {I list GOVERNMENT PRINTlNG UFFICE: 969 0-353-33,

3,658 l47 April 25 1972 Charles Bancroft PAGE 2 edge 114 defined by an axial plane and along their counterclockwise edges by a helical edge 116 of extremely steep pitch, diverging from an axial plane by only a few degrees to provide a "tapered" cam'ming or latching surface.

The next adjacent sector segments 117 are positioned around the inner periphery of a locking ring 118 and are dimensioned for telescoping engagement beside the adjacent sector locking ring segments 113. The sector segments 117 are bounded along their clockas viewed in FIGURE" l0, and along their opposite counterwise edges by slanting or steeply pitched helical surfaces 119,

clockwise edges by axial surfaces defined by an axial plane 121.

Slight counterclockwise rotation of ring 118 relative to stepped bridge member 89 allows these two members 89 and 118 to be telescoped together, with flanges 117 and 1153 closely adjacent.

Clockwise rotation of ring 118 relative to stepped bridge member 89 then brings the helical bounding surfaces 119 of sector segments 117 into abutting juxtaposition with the helical bounding surfaces 116 of sector segments 113, providing the maximum angular separation between the non-abutting edges of these sector ring segments, the edges 114 and 121. This maximum angular separation provides space for angular sector flanges 122 protruding axially from sidewall member 88 toward sidewall member 74 to be moved axially into telescoping engagement therebetween.

Accordingly, when sector segments 122 are slidingly telescoped into position, the sector segments 113, 117 and 122 A ril 25.? 197 3 65894? was 3 Charles Bancroft successively complete the entire locking ring assembly around the inner periphery of the device, Locking bolts. 124 telescopingly 122 engage tapped aligned apertures 126 in locking ring 118. The

anchoring bolted engagement of left outer sidewall 88 to ring 118 in the assembled position secures sector segments 12 closely juxtaposed to the sector segments 117 of the locking ring, preventing withdrawal of ring 118 from its telescoping engagement encircling flange sectors 113 of stepped bridge member 89 by reason of the interfering engagement of the abutting helical bounding I surfaces 116 and 119.. The application of force tending to withdraw ring 118 from step bridge member 89 produces "ramp-canning or jamming engagement of helical surfaces 116 and 119, merely serving to force the sector segments 113, 117 and 122 into tighter angular juxtaposition around the periphery of the assembled parts encircled by ring 118. Only the removal of the bolts securing left outer sidewall member 88 to ring 118 by virtue of the aligned apertures 123 and 126 permits the separation of these assembled parts,

3 6585 447 v I A ril 2 1 2 Charles Bancroft Pit-FE 4 5, 97

The spline and lock ring assembly employed to secure the right inner sidewall unit 74 in assembled relationship with the driving mechanism is shown in FIGURE 1 and in the enlarged views of, FIGURES 6 7 and 8., In these figures, it will be noted that the rim of flange 78 of sidewall unit 74 remote from the vane piston chamher is provided with axially protruding L-shaped projections l2! These projections 127 are angularly spaced apart subtending short angular sectors of the periphery of flange 78 and spaced apart by similar sectors, forming a lo- -tooth spline A driving disk 129 incorporating radial crosshead slideways to receive the pillow block bearings is providedwith radially protruding mating peripheral spline projections 131 angularly spaced and dimensioned for interfitting engagement "between the projections 127. Aligned slots 134 accommodating a latching ring; 136, are formed facing radially outward in projections l27 and 131. When split latching ring 136 is slipped into the aligned slots 134, itsnatural resilience draws the ring 136 elastically into slot 134 behind the flanges of both projections, thus tending to hold drive disk 129 in its assembled position. An additional securing ring 137 which may be Le-shaped in cross-section is installed encircling dim...

, the outer periphery of ring 136 to complete the assembly,

April 25, 1972 PAGE 5 Charles Bancroft and the internal diameter of ring 137 is preferably slightly smaller than the unstressed, relaxed external diameter of ring 136," assuring that split resilient ring 136 provides a self-biasing, resilient, radial force against the internal rim of ring 137, securing the entire latching assembly in the assembled relationship illustrated in FIGURES 1,7 and 8.

Since the foregoing description and drawings are merely illustrative, the scope of the invention has been broadly stated herein and it should be liberally interpreted to secure the benefit of all equivalents to which the invention is fairly entitled.

What is claimed is:

,6 8,447 pri 5, v hailes Bancroft r .6 H I ln an alternately accelerating rotary piston device of the character described, including a stator housing 7 containing an annular chamber and a plurality of sets pf angula'rly -spaced vane pistons successively arrayed in tl'e chamber, each set having at least two vanes secured to a support member and all sets having their relative angular positions determined by connecting members interconnecting the support members to a crankshaft, the improvement comprising A. a pair of said piston support members form ing unitary sidewall members respectively positioned at each axial end of the annular chamber and extending radially alongside opposite ends of all vane pistons therein,

B. a at" least a first one of the sidewall support members being axially connected to an outer end wall positioned at the opposite end of the annular chamber beyond and in adjacent axial juxtaposition behind the second sidewall support member,

forming therebetween an axially expansible sealing pressure chamber, 

1. In an alternately accelerating rotary piston device of the character described, including a stator housing containing an annular chamber and a plurality of sets of angularly spaced vane pistons successively arrayed in the chamber, each set having at least two vanes secured to a support member and all sets having their relative angular positions determined by connecting members interconnecting the support members to a crankshaft, the improvement comprising A. a pair of said piston support members forming unitary sidewall members respectively positioned at each axial end of the annular chamber and extending radially alongside opposite ends of all vane pistons therein, B. at least a first one of the sidewall support members being axially connected to an outer end wall positioned at the opposite end of the annular chamber beyond and in adjacent axial juxtaposition behind the second sidewall support member, forming therebetween an axially expansible sealing pressure chamber, C. the first sidewall support member and its axially connected outer endwall being connected for simultaneous axial movement, and restraining each other against individual axial movement, D. the outer endwall and the adjacent second sidewall support member being provided with slidingly engaged axially extending flange means providing axial sliding chamber-expansion movement therebetween.
 2. The device defined in claim 1, further including means confining any gases leaking past the radially innermost portions of said sidewall support members and directing said leaking gases into said axially expansible sealing pressure chamber.
 3. In an alternately accelerating rotary piston device of the character described, including a stator housing containing an annular chamber and a plurality of sets of angularly spaced vane pistons successively arrayed in the chamber, each set having at least two vanes secured to a support member and all sets having their relative angular positions determined by connecting members interconnecting the support members to a crankshaft, the improvement comprising A. a pair of said piston support members forming unitary sidewall members respectively Positioned at each axial end of the annular chamber and extending radially alongside opposite ends of all vane pistons therein, B. at least a first one of the sidewall support members being integrally connected to an outer end wall positioned at the opposite end of the annular chamber beyond and in adjacent axial juxtaposition behind the second sidewall support member, forming therebetween an axially expansible sealing pressure chamber, C. the outer endwall and the adjacent sidewall support member being provided with slidingly engaged axially extending flange means providing axial sliding chamber-expansion movement therebetween, D. and vent channel means connected to convey leakage gas escaping from the annular chamber into the sealing pressure chamber, tending to separate the endwall and the adjacent sidewall support member.
 4. The device defined in claim 3 wherein each of the two sidewall support members is integrally connected to one outer endwall positioned at the opposite end of the annular chamber beyond and in adjacent axial juxtaposition behind the other sidewall support member, forming an axially expansible sealing pressure chamber between each sidewall support member and its adjacent endwall.
 5. The device defined in claim 3 wherein each sidewall support member is positioned in sliding abutting juxtaposition at the axially outermost end of a central hub-type support member, and wherein the vent channel means comprise passageways extending through the sidewall support member and connecting portal ends thereof exposed to the abutting juxtaposed hub-type support member with discharge ends exposed to the sealing pressure chamber, whereby leakage gas escaping from the annular chamber between the sidewall support member and the juxtaposed hub-type support member is conducted into the sealing pressure chamber, urging each of the sidewall support members simultaneously into closer sliding abutting engagement with the end of the hub-type support member juxtaposed therewith.
 6. The device defined in claim 3 wherein each sidewall support member is positioned in sliding abutting juxtaposition at the axially outermost end of a central hub-type support member, and wherein the outer end wall is axially movable and is provided with an axially extending flange slidingly and sealingly engageable with the adjacent hub-type support member, thereby enclosing a gas conducting vent channel passageway formed between the associated sidewall support member and its abutting hub-type support member, so that gas escaping from the piston chamber as a result of axial separation of the sidewall support members is conducted primarily into the sealing pressure chamber.
 7. In an alternately accelerating rotary piston device of the character described, including a stator housing containing an annular chamber and a plurality of sets of angularly spaced vane pistons successively arrayed in the chamber, each set having at least two vanes secured to a support member and all sets having their relative angular positions determined by connecting members interconnecting the support members to a crankshaft wherein the stator housing forms an outermost peripheral bounding wall of the annular chamber, the improvement comprising A. a pair of said piston support members forming sidewall members respectively positioned at each axial end of the annular chamber and extending radially into slidingly sealed engagement with the outermost peripheral bounding stator housing wall; B. means forming a plurality of sealing ring grooves encircling the periphery of each sidewall support member facing the stator housing wall; C. a corresponding plurality of sealing rings positioned in the encircling grooves and protruding radially therefrom into sliding sealing engagement with the stator housing wall; D. an axially innermost first sealing ring groove formed in each sidewall support member adjacent to the annular chamber and separated therefrom by a sealing flange having crenel apertures formed therein joining the first sealing ring groove with the annular chamber periphery, angularly spaced about substantially the entire periphery of the sidewall support member not occupied by pistons supported thereby; E. and a first sealing ring positioned in the first sealing ring groove and provided with projections aligned with and extending axially through the crenel apertures into angular sliding sealing engagement with the juxtaposed end walls of the pistons not supported by the sidewall member in which the crenel apertures are formed; whereby gas pressures occurring in adjacent annular chamber sectors on opposite sides of a vane piston are confined between each crenel aperture and its engaging projection, maintaining each chamber sector in pressure sealed integrity substantially isolated from the adjacent chamber sectors.
 8. The device defined in claim 7 wherein the crenel apertures are formed as radially diverging apertures substantially trapezoidal in cross-section, and the projections on the first sealing ring extending therethrough are formed with correspondingly shaped trapezoidal cross-sections.
 9. The device defined in claim 7 wherein the crenel apertures are formed as radially diverging apertures separated by gear tooth-shaped merlons extending radially outward therebetween, and the first sealing ring projections extending therethrough are formed with gear-tooth shaped cross-sections for intermeshed engagement with the merlons.
 10. The device defined in claim 7 wherein the first sealing ring is a divided ring having a circumference less than a complete circle.
 11. The device defined in claim 7 wherein the first sealing ring comprises a plurality of angular sectors arrayed end-to-end in the first sealing ring groove.
 12. The device defined in claim 11 wherein the sealing ring sectors each extend between the midpoints of adjacent pistons of the vane piston set secured to the sidewall support member carrying the sealing ring sectors.
 13. The device defined in claim 11 wherein the radius of curvature of the sectors is less than that of the bounding stator housing wall, and wherein the ends of the sectors are resiliently biased radially outward into engagement therewith.
 14. The device defined in claim 13, further including compression springs each positioned in a peripheral recess formed in the sidewall support member underlying the adjacent ends of two ring sectors and resiliently compressed therein to impose radial outward force urging the ring sector ends outwardly toward the outermost bounding chamber housing wall.
 15. The device defined in claim 14 wherein each peripheral recess is angularly positioned at the midpoint of a vane piston secured to the sidewall support member carrying the sealing ring sectors. 